Now it is bright as 8.9 mag (June 4, Chris Wyatt). It stays bright as 9 mag for a while. In the Southern Hemisphere, it stays observable in good condition for a long time until the comet will fade out. In the Northern Hemisphere, it is observable only until June.

Now it is not observable. It will brighten up to 9 mag in summer, but it is hardly observable when it is bright. In the Northern Hemisphere, it is not observable until late December. In the Southern Hemisphere, it is observable from July to September, but it locates in extremely low.

It brightened rapidly as expected. Now it is very bright as 10.7 mag (May 25, Chris Wyatt). It stays at 10-11 mag until June. In the Southern Hemisphere, it stays observable in excellent condition. In the Northern Hemisphere, it will be unobservable from April to June when the comet becomes brightest.

Now it is 11.3 mag (May 15, Juan Jose Gonzalez). It stays bright as 11 mag for a long time until autumn. In the Southern Hemisphere, it is not observable for a long time after this. In the Northern Hemispehre, it stays observable for a long time until the comet fades out. But it stays very low until autumn.

First return of a new periodic comet which brightened up to 13 mag in 2013. Now it is 14.2 mag (June 3, Michael Mattiazzo). It will brighten very rapidly after this, up to 11 mag in summer. In the Southern Hemisphere, it stays observable in good condition all through this apparition. In the Northern Hemisphere, it is not observable at the high light from mid June to mid August.

Now it is 14.4 mag (May 21, Toshihiko Ikemura, Hirohisa Sato). It will brighten rapidly, and brighten up to 7 mag from August to September. In the Northern Hemisphere, it will be observable in excellent condition. In the Southern Hemisphere, it will be unobservable from July to August. But it will be observable in good condition before and after tha.

Now it is 11.6 mag (May 15, Juan Jose Gonzalez). It stays 12 mag for a long time until spring in 2019. In the Northern Hemisphere, it stays observable in good condition for a long time, although it becomes unobservable temporarily from mid June to August. In the Southern Hemisphere, it is not observable until September.

Now it is 14.7 mag (May 21, Catalina Sky Survey). It will brighten rapidly after this, and it will brighten up to 11 mag from summer to autumn. It is observable in excellent condition in the Southern Hemisphere. It locates somewhat low in the Northern Hemisphere.

It is expected to approach to Sun down to 0.2 a.u. and brighten up to 3 mag in August. Now it is 16.4 mag (May 17, Toshihiko Ikemura, Hirohisa Sato). In the Northern Hemisphere, it stays observable in the morning sky until early August when the comet brightens up to 6 mag. It is not observable at all in the Southern Hemisphere.

Now it is very bright as 12.0 mag (May 15, Juan Jose Gonzalez). It will be observable at 12-13 mag for a long time from 2017 to 2018. In the Southern Hemisphere, it will be hardly observable after this.

Now it is 14.8 mag (May 14, Toshihiko Ikemura, Hirohisa Sato). It will brighten up to 13 mag in 2019 spring. In the Northern Hemisphere, it stays observable in good condition for a long time. In the Southern Hemisphere, it locates extremely low until summer.

It brightened very rapidly. Now it is very bright as 11.8 mag (May 16, Juan Jose Gonzalez). It may fade out very rapidly in June. In the Northern Hemisphere, it stays observable until it fades out. It is not observable in the Southern Hemisphere.

Now it is 15.2 mag (May 21, Martin Masek). It stays 15 mag from 2018 to 2019, and it will be observable for a long time in the Southern Hemisphere. In the Northern Hemisphere, it will never be observable again.

It brightened up to 7.1 mag from May to June in 2017 (June 21, Juan Jose Gonzalez). Now it is fading. It has already faded down to 14.6 mag (May 14, Thomas Lehmann). In the Southern Hemisphere, it stays observable for a long time after this. It will never be observable again in the Northern Hemisphere.

Now it is 20.7 mag (May 25, J. V. Scotti). It will brighten rapidly, and it is expected to brighten up to 10 mag in autumn. But actually, it is much fainter than this ephemeris. It will be observable in excellent condition in the Northern Hemisphere. It stays low in the Southern Hemisphere.

Now it is 17.2 mag (May 19, CAO, San Pedro de Atacama). Fading now. It stays observable in good condition for a long time after this in the Southern Hemisphere. It is not observable until June in the Northern Hemisphere.

Now it is 15.5 mag (Mar. 16, iTelescope Observatory, Siding Spring). It brightens up to 16 mag in spring. In the Southern Hemisphere, it stays observable until August, but it will be unobservable after that. In the Northern Hemisphere, it stays unobservable until June, but it will be observable in good condition after that. Its cometary activity was observed on Mar. 26 (M. Mommert, D. Polishook, N. Moskovitz).

Now it is 16.7 mag (May 13, Hidetaka Sato). It will brighten rapidly after this, and it is expected to brighten up to 9 mag from autumn to winter. In the Northern Hemisphere, it stays observable in good condition for a long time until it fades out. In the Southern Hemispehre, it is observable in good condition until autumn, but it will be low in winter.

Now it is 17.2 mag (May 21, Toshihiko Ikemura, Hirohisa Sato). It was observed at 16 mag from summer to autumn in 2017. It will be observable at 16.5 mag in good condition also in 2018. It locates somewhat low in the Southern Hemisphere.

Now it is 16.7 mag (May 10, Toshihiko Ikemura, Hirohisa Sato). It will brighten up to 15 mag in January, 2019. It stays observable in excellent condition in the Northern Hemispehre. It is observable only until June in the Southern Hemisphere.

Now it is 16.8 mag (May 15, Toshihiko Ikemura, Hirohisa Sato). It will be fading gradually after this, and it will be fainter than 18 mag in winter. In the Northern Hemisphere, it stays observable in good condition for a long time. In the Southern Hemisphere, it will never be observable again.

Now it is bright as 18.0 mag (May 14, Hidetaka Sato). Hidetaka Sato pointed out its cometary activity. In the Northern Hemisphere, it stays observable at 18 mag until June. It is not observable in the Southern Hemisphere.